WTC Concrete pulverization

Originally posted by BigTrain
This is quite comical. A few months ago, BSbray was posting all these posts on "how come the buildings collapsed on their own footprint then?" Now he is trying to justify his position on the fact that the buildings DID NOT collapse onto their own footprint, even posting photos that prove material was ejected outward which proves my point I was making against him a while back.

And your understanding of this situation bsbray is a joke. You keep contradiciting yourself time and time again. How many different scenarios are you going to enbrace until you decide on a definitive cause? At least pick one collapse theory and stick to it, it will make you seem at least more respectable, but as far as im concerned, you have no moral ground to stand on.

BSB flipflops more than Kerry.

Train

In his defense, I have NEVER heard him argue that the towers fell into their footprints. Simetrical yes, but not in their footprints. Care to provide a post that he has said this? But like everything else I ask you to provide, you'll just probably ignore me.

Also, I keep hearing things from you with no proof to back up anything you say. Where's your structural calculations? I've been asking you for these for at least 6 months now.

Also, I guess "staying the course" is a respectable thing to do? Even if you have been proven wrong? Maybe BSBray changes his theory when new evidence comes out. But, I guess going by your thinking, the world is flat?

watch the videos it is not so discrete. squibs are clearly visable and i would trust a joe smoes word over the goverments any day and when alot of people say they heard explosions i tend to lean that way.

The centers of gravity would have been in the footprints because all of the debris fell around the footprints.


Big Train's problem is that he doesn't understand the difference between center of gravity, and where most of the debris itself actually landed. Hope that clears that up.

[edit on 9-11-2006 by bsbray11]

On page 20 in the second paragraph the author uses the word assume.

This sums up the report. It is an assumption.

To have one building fall in a near perfect manner is amazing, to have two do it, without the same exact amount of damage is impossible.

[edit on 9-11-2006 by Wolfpack 51]

Originally posted by Wolfpack 51
To have one building fall in a near perfect manner is amazing, to have two do it, without the same exact amount of damage is impossible.

Not to mention the third that fell that day. But WTC 7 is another story.

You CT's can never keep it on topic can you?

NO ONE'S talking about WTC7. Leave it out of the thread. Far out...

Howard you get my WATS vote mate. Your argument is far more convincing than bsbrays. Well done.

greening's energy transfers leave one hundred percent of the mass in the footprint, as he never allows for the fact that 90% of the debris was outside the footprint.

greening's initial impact focuses one hundred percent of the energy of the upper mass onto the 'floor', completely ignoring the vertical columns, and the impossible geometry of fitting something of a given size into something else of an equal size.

greening still uses the 3.7 (near) freefall initial drop.

greening ignores gordon ross' FAR more realistic momentum transfers.

greening doesn't mention the fact that more than concrete was instantly turned into dust IN HIS MATH. he allows only for the comminution of concrete, while ignoring the other 60% of the fine dust. okay, gypsum is not that hard to pulverize, but wood and paper and PEOPLE(also not mentioned in the dust anaylsis from greening, but WAS in the actual study) sure as hell are.

greening ignores the fact that the falling part is the first to be destroyed, prefering to use one floor up, one floor down.

greening admits, that even in his totally unrealistic model, the velocity should have been halved after the first impact(while of course, ignoring that the core is 'unhingeable' with it's continuously welded box columns, and never could have 'snapped' and gone into near freefall), and yet, that is not what is observed on video.


it's a losing battle. i don't know why greening wants to dig himself in deeper. he should just admit he's using unreal assumptions not grounded in reality. he contradicts himself by using all the falling masses' energy for crushing and bending and breaking(while using an unreal safety factor of 2), and then goes on to admit openly that most of the mass was not within the footprint.

posted by sir isaac frickin' newton (aka moi) at physorg, earlier today(yesterday, for some).

Originally posted by doctorfungi
You CT's can never keep it on topic can you?

NO ONE'S talking about WTC7. Leave it out of the thread. Far out...

Howard you get my WATS vote mate. Your argument is far more convincing than bsbrays. Well done.

And when some see that science and math seem to be on the "CT'er's" Side, the immediately pull a 9/11 and ignore the facts, science and math of it all.

Good Job there Fungi, you get nothing from me except ignorance.

As for the post at hand. I would like you guys to look at g210b other post located here.

www.abovetopsecret.com...

It is really interesting in his findings. Pretty much replicates Scholars dead on.

When in doubt use science man Science is the key.. and a little math.

Originally posted by bsbray11
That's not just concrete.

In fact, no concrete at all is shown there, as it went MUCH farther, carried in massive dust clouds by the wind.

In fact, that's just where most of the STEEL and aluminum cladding landed. And we've already seen in actual images of Ground Zero that all of this debris was flung all over the complex and beyond, not just sitting in a big pile at the bases as you're trying to suggest. It was the steel and aluminum and concrete (turned to dust) and ALL that was sent outwards in so many directions.

while i completely agree that buildings don't just pulverize themselves, i will have to add that there were basement below the WTC, likely accounting for the bulk of the towers' mass.

the doustclouds were probably intentional, to conceal as much as possible from public view.

How u going,

I quickly skimmed over the report that was posted in the original message, and the first two things came to mind;

Who is this person that wrote the article? (obviously no one too important, no Dr. or Prof etc.)
and
IF they knew anything about concrete they would have mentioned or referenced an article that spoke of the behaviour of concrete under blast loads.

My apologies if they did.

I am a civil engineering student (graduating in 2weeks!, cant wait lol) from Australia, and I have done numerous topics in concrete and steel, my uni loves it, and I have mentioned in another thread that our uni is actually responsible for the delivery of the Australian Standards and other such material that is produced by the Aust. Inst of Eng's in regard to concrete and steel.

That said, concrete behaves very differently when subjected to larger loads and forces over different time spans, some of you might know about concrete creep, whereby concrete effectively 'shrinks' over time, subject to a constant load.

So, my points are;

1)This guy who wrote the report, in my opinion has no credentials
2)If the report meant anything he wouldve had to have mentioned blast loading
3)As much as I would like to believe that the towers were brought down by explosives, they werent, a plane hit them at twice the speed and of twice the weight then the towers were designed to withstand blah blah blah (as by many reports out there)

Hey, d3. Thank you very much for your learned input on this. As is the case even with analyzing steel structures versus concrete, the dynamic loading has to be taken into account because impact loading changes the response behavior of just about any material you want to talk about.

I look forward to reading more of your posts in the future. Even though it's belated, welcome to ATS.

The debris pile was at least 5-7 stories abouve ground.
The debris pattern shown by the red circles is inaccurate, debris covered all of downtown Manhattan. There was a few inches covering everything after the second tower fell.

There were no explosions.....considering that I was there 1 1/2 blocks away watching the tower fall getting covered by all the debris.

If you were in the lobby of a building over 1,000 feet tall and it started to collapse 900 feet about your head.....what do you think it would sound like?.....a bunch of explosions maybe......you have steel snapping, concrete breaking and everything being destroyed.

Originally posted by d3si1r3
1)This guy who wrote the report, in my opinion has no credentials

Frank R. Greening was born in London, England in 1947. He has a Ph.D.
in physical chemistry and has carried out research in physics,
chemistry, and materials science for 30 years in academic and
industrial positions. He has published approximately 80 research
reports and journal articles, including numerous articles supporting
the government's collapse sequence theories of World Trade Center
Buildings 1 & 2.

source


In his own words:

I am a retired nuclear scientist with 23 years experience working for OPG’s Research Division in Toronto. I have spent most of my professional career dealing with technical problems with OPG’s fleet of CANDU reactors at Pickering, Bruce and Darlington.

source

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Originally posted by d3si1r3
2)If the report meant anything he wouldve had to have mentioned blast loading

From the above linked paper:

V. M. Kuznetsov. “The Mean Diameter of the Fragments Formed by Blasting Rock.”
Soviet Mining Science Vol. 9(2), 144, (1973).
A. Rustan. “The Influence of Specific Charge, Geometric Scale and Physical Properties
of Homogenous Rock on Fragmentation.” Proceedings of the First International
Symposium on Rock Fragmentation by Blasting, page 114, (1983).
B. M. Luccioni et al. “Concrete Pavement Slab Under Blast Loads.” International Journal
of Impact Engineering, Vol. 32, 1248, (2006).

Were those what you were talking about?

If you have a better reference source, his e-mail address is in the paper. I’m sure he would appreciate the info.

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Originally posted by d3si1r3
3)As much as I would like to believe that the towers were brought down by explosives, they werent, a plane hit them at twice the speed and of twice the weight then the towers were designed to withstand blah blah blah (as by many reports out there)

At least you got that part right.

Originally posted by d3si1r3
That said, concrete behaves very differently when subjected to larger loads and forces over different time spans, some of you might know about concrete creep, whereby concrete effectively 'shrinks' over time, subject to a constant load.

Actually concrete shrinks over time period. It doesn't have to be loaded. That's why concrete has shrinkage cracks in it. Even facade panels that are not loaded have shrinkage cracks.

Welcome to ATS. From one civil engineer to another.

I look forward to debating with you in the future. I might actually learn a few things, being as you are fresh out of school.

Originally posted by ferretman2
There were no explosions.....considering that I was there 1 1/2 blocks away watching the tower fall getting covered by all the debris.

So, you are contradicting all the other eye witnesses and reporters that reported explosions? You didn't hear anything? BTW, these reports are before the buildings collapsed. I'm not saying explosives were the cause but to say there were no explosions is just misrepresenting what happened IMO.

Also, if there were no explosions, how do you explain the damage in the basements and lobbies?

One interesting aside (This has nothing to do with the WTC towers that I know of, but it is illustrative of how building technology changes over time for good and bad)

A few years back, I did some work in a building designed by Mies Van der Rohe and build at about the same time as the towers (Late ‘60s). Anyway, when the building was built, they used accelerators in the concrete mix to facilitate pouring of the floor slabs in colder weather. Now they were now having problems (25 years later) as a result. It seems that the chlorides from the accelerator were causing excessive corrosion to the mesh rebar which was causing unacceptable spalling as a result.

There were numerous repair projects throughout the building as a result.

The history of building design and construction is littered with ideas that seemed brilliantly innovative at the time, but turned into debacles over time.

This is all straying from the subject a bit, so I’ll stop here.

Actually Howard, you bring up an excellent point. Too bad we don't know the exact mix that went into the towers. Like what was the water-to-cement ratio, what aggregates (did they use perlite or some other fiber for the lightweight concrete?), any accelerators, etc.

no wonder they had to shut down the pickering plant.
greening consulting on nuclear power plants?

*shudder*

it amazes me how bozos can go through a whole career, and actually get good work, when they're bozos, and always will be.

greening, the man who entered the 911 fray with 'coincidental thermite'(which of course, is not needed, as gravity alone will do, according to later greening). greening, the man who explains that 120, 000 tonnes of dust(by his estimate) is spread all over lower manhatten, and yet uses 100% of that mass in his calculations of kinetic energy for tower destruction.

i think i'll go get a drink of heavy water from lake ontario.

Originally posted by Long Lance
while i completely agree that buildings don't just pulverize themselves, i will have to add that there were basement below the WTC, likely accounting for the bulk of the towers' mass.

It'd be hard to prove or disprove exactly how much went into the sublevels, which were constructed a whole lot more heavily than any of the upper floors.

Note that the basements couldn't have been totally cleared out, because core columns still stood at WTC1 and WTC2's bases, running into the basements/foundations:





And here are some photo comparisons of excavations of the basements (from the clean-up):








Other parts of Ground Zero:






Like I said, it would be hard to prove or disprove what went down there when you can't see the whole thing, but I'm not seeing any major debris down there besides still-standing core columns going into the foundations and a few I-beams here and there that were probably lateral bracing (but not trusses) from the lowest above-ground floors or even the basements themselves. A lot of pulverized concrete and rebar, though.

Bsray -

The picutres from above really do not do any justice to what the area acutally looked like.

There was sh*t literally everywhere. It was such a large mess over a 16 acre area.

You need picutres from ground level prior to the clean-up beginning to even start to get a sense of what it was like.